The present invention relates to lawn mowers and particularly an auxiliary mower for use with self-propelled lawn mowers of the garden tractor type for permitting the operator to cut a wide range of types of vegetation such as grass, weeds, light brush and vines as found in lawns and adjacent areas and also for cutting vegetation around plants, trees, shrubs, etc. or other areas inaccessible for garden tractor types.
In particular, the present invention is directed to small tractors preferably of the garden type wherein the invention may be readily attached and detached therefrom and therefore serves as an auxiliary mowing apparatus in the form of an attachment mechanism.
In the art of auxiliary mowing apparatus arranged for attachment to a conventional tractor, the mechanisms utilized are either overly complicated and massive with regard to the specific structures utilized, and therefore are unsuitable for garden tractors, or the auxiliary mowing mechanisms are relatively limited as to the extent to which the cutting apparatus associated therewith is capable of reaching without overextending the operation of the host tractor. An example of the first category is illustrated and described in U.S. Pat. No. 2,451,589 to Thomas and comprises numerous wheeled frames interconnected by a supply of belts and chains and comprising parts which are relatively large and difficult to assemble and disassemble with respect to a host tractor. Similarly, the device described in U.S. Pat. No. 1,297,628 to Wodham comprises large apparatus interconnected by numerous drive devices for effecting the broad expanse of cutting capabilities of an area to be mowed.
In U.S. Pat. No. 2,791,953 to Erickson et al., a cultivator is described which is adapted to maneuver a cutting device around posts and row crops. However, the cultivator is not specifically adapted to be easily moved from one side of the tractor to the other in a semicircle which includes the area to the rear of the tractor. In addition, a mechanism for operating the cutting device comprises a hydraulic circuit which, although directly accessible to an operator seated on the tractor, nevertheless is relatively complex and costly for an auxiliary mowing machine particularly adapted for the ordinary garden tractor.
An example of the second category of attachment devices comprising mowing mechanisms for garden tractors is found in U.S. Pat. No. 3,508,384 to Madre. This patent illustrates and describes an auxiliary mowing mechanism for a garden tractor which, while fairly simple as to parts and efficiency, is not readily adapted for easy movement of the cutting apparatus from one side of the tractor to the other side in an arc defined perpendicular to the direction of movement of the tractor. Similarly, U.S. Pat. No. 3,624,698 to Storm describes a mowing attachment for a small tractor but is not provided with an arrangement whereby the cutting device may be easily swung from side to side of the tractor without detaching or attaching structures related thereto.
Therefore, one of the principal objects of the present invention is to improve tractor drawn lawn mowers or auxiliary cutting apparatus which may be swung from one side of the tractor to the other to enlarge the area for cutting during a cutting run by the tractor.
Another principal object of the present invention is to permit the easy and quick adjustment by an operator sitting on the tractor to manipulate a selected positioning of the cutting apparatus as the tractor is being moved.
A further principal object of the present invention is to provide an auxiliary cutting apparatus which can move vertically to adjust to terrain at different heights, yet is biased toward the ground so as to be sufficiently stable during operation to avoid a hazardous condition of exposing the cutting mechanism during the vertical adjustments of same that occur while traversing uneven terrain.
A still further principal object of the present invention is to lower the cost for auxiliary lawn mowers adapted for a wide range of cutting positions.
Another principal object of the invention is to arrange for permitting the grass cutting apparatus to be quickly and easily attached to or removed from the tractor.
Additional objects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out herein.
To overcome the above disadvantages and problems with conventional auxiliary lawn mowers for use with garden tractors and to accomplish the foregoing objects, the present invention has been devised so that an auxiliary lawn mower is adapted to be operatively connected to a tractor at a single point, such as a connection to the conventional hitch associated with the tractor. The auxiliary cutting apparatus of the present invention includes a wheeled trailer frame arranged to be directly and pivotally connected to the tractor's hitch. The trailer frame preferably includes a platform so that the wheeled platform serves as a support for the cutting apparatus. The trailer is provided with a vertically arranged pivot member which supports a cutter boom frame so that the cutter boom frame may be rotatably related to the trailer. The boom extends in opposite directions from the point where it is pivotally supported. Means for cutting vegetation, such as grass, weeds, light brush and the like, is mounted on one end of the cutter boom frame. Preferably, the cutting means includes a cutter apparatus of the rotary blade type that is pivotally mounted vertically for application to lawns or other areas and vegetation to be cut. The end of the cutter boom which carries the cutting means also has a wheel which supports the extended end of the cutter boom for movement across the ground or area to be cut and is arranged so that the plane of the cutter blade is supported at a cutting height above the area to be cut and preferably variably related as to such height. The opposite end of the cutter boom supports means for supplying power for imparting cutting action to the cutting means. Preferably, the power means includes an internal combustion engine, such as a gasoline motor, and a pulley therefor which is directly connected to a similar pulley operatively associated with the cutter blade at the other end of the cutter boom.
The cutter boom is adapted for swiveling action about the pivot axis of the pivot member on the trailer. Means are provided for pivoting the boom frame relative to the trailer frame over a range of from 0 to 280 degrees. Preferably, the pivoting means includes the pivot member and a closed loop drive element that engages a drive pulley or sprocket which is nonrotatably related to the boom frame. The pivot member is rotatable with respect to one of the trailer frame and the boom frame and nonrotatable with respect to the other of the trailer frame and the boom frame, whereby rotation imparted by the drive element effects pivotal movement of the boom frame with respect to the trailer frame. Preferably, the drive element includes a plurality of links joined together to form a chain that engages a drive mechanism in the form of a pulley or sprocket nonrotatably mounted to either the cutter boom frame or the pivot member. Rotation of this pulley or sprocket results in rotation of the cutter boom frame, which is nonrotatably related to such pulley or sprocket.
Means are provided for activating the pivoting means to selectively pivot the boom frame in a horizontal plane for moving the cutting means to selected cutting positions. As embodied herein, the activating means includes a pulley or sprocket rotatably mounted near the end of the trailer frame connected to the tractor. The drive element also engages this pulley or sprocket. A manually operable crank is connected to the trailer frame pulley or sprocket for direct operation by the operator while sitting on the tractor seat. In this arrangement, the cutter boom is adapted for complete and reversible swiveling action from one side of the tractor to the other side and is capable of cutting the approximately 280 degree area encompassed by its full swiveling action.
In addition, means preferably is provided for pivotally mounting the boom frame in a vertical plane thereby permitting the raising and lowering of the cutting means. As embodied herein, the means for permitting the raising and lowering of the cutting means preferably includes a pair of depending flanges disposed from beneath the boom frame and pivotally connected to a U-shaped member disposed at one end of the pivot member. A pivot pin extends through aligned openings in the flanges and U-shaped member, and the boom frame pivots about the longitudinal axis of the pivot pin to raise and lower the cutting means disposed on one end of the boom frame. Preferably, the boom frame is mounted on the pivot pin whereby the boom frame balances the weight of the cutting means and the power means so as to bias the cutting means towards the ground.
The objects of the invention mentioned above and other objects of the present invention will become apparent after reading the following written description taken in conjunction with the drawings, which are incorporated in and constitute a part of this specification. The accompanying drawings illustrate preferred embodiments of the invention and, together with the description, serve to explain the principles of the invention.